Implement C Declarations5 package

.vscode/tasks.json

@@ -206,6 +206,7 @@
                 "Declarations",
                 "Declarations1",
                 "Declarations2",
+                "Declarations5",
                 "Exceptions1",
                 "Exceptions2",
                 "Expressions",

c/common/test/rules/unnecessaryexposedidentifierdeclarationshared/UnnecessaryExposedIdentifierDeclarationShared.expected

@@ -0,0 +1,4 @@
+| test.c:4:12:4:13 | g2 | The declaration g2 should be moved from the global namespace scope$@ into the $@ too minimize its visibility. | file://:0:0:0:0 | (global namespace) | scope | test.c:59:11:59:25 | { ... } | scope |
+| test.c:7:7:7:7 | j | The declaration j should be moved from $@ into the $@ too minimize its visibility. | test.c:6:11:13:1 | { ... } | scope | test.c:8:13:12:3 | { ... } | scope |
+| test.c:62:7:62:7 | i | The declaration i should be moved from $@ into the $@ too minimize its visibility. | test.c:61:11:71:1 | { ... } | scope | test.c:64:13:70:3 | { ... } | scope |
+| test.c:73:8:73:9 | S1 | The declaration S1 should be moved from the global namespace scope$@ into the $@ too minimize its visibility. | file://:0:0:0:0 | (global namespace) | scope | test.c:77:12:77:28 | { ... } | scope |

c/common/test/rules/unnecessaryexposedidentifierdeclarationshared/UnnecessaryExposedIdentifierDeclarationShared.ql

@@ -0,0 +1,2 @@
+// GENERATED FILE - DO NOT MODIFY
+import codingstandards.cpp.rules.unnecessaryexposedidentifierdeclarationshared.UnnecessaryExposedIdentifierDeclarationShared

c/common/test/rules/unnecessaryexposedidentifierdeclarationshared/test.c

@@ -0,0 +1,110 @@
+#include <stdbool.h>
+extern void f1(int i);
+extern int g1; // COMPLIANT
+extern int g2; // NON_COMPLIANT; single use of a global variable
+bool f2() { return g1 == 1; }
+void f3() {
+  int j = g1; // NON_COMPLIANT
+  if (f2()) {
+    int k; // COMPLIANT
+    f1(j);
+    f1(k);
+  }
+}
+
+void f4() {
+  int j = g1; // COMPLIANT; value of g1 changed between
+              // definition and use
+  g1 = 1;
+  if (f2()) {
+    f1(j);
+  }
+}
+
+void f5() {
+  int j = g1; // COMPLIANT; shouldn't be moved inside loop
+  while (true) {
+    int i = g1++;
+    while (f2()) {
+      i += j;
+    }
+
+    if (i % 2)
+      break;
+  }
+}
+
+void f6() {
+  int j = g1; // COMPLIANT; can't moved into smaller scope
+#ifdef FOO
+  if (g1) {
+    g1 = j + 1;
+  }
+#else
+  if (g1) {
+    g1 = j + 2;
+  }
+#endif
+}
+
+void f7() {
+  int j = g1; // COMPLIANT; potentially stores previous value of
+              // g1 so moving this would be incorrect.
+  f1(1);      // f1 may change the value of g1
+  if (f2()) {
+    f1(j);
+  }
+}
+
+void f8() { int i = g2; }
+
+void f9() {
+  int i; // NON_COMPLIANT
+
+  if (f2()) {
+    if (f2()) {
+      i++;
+    } else {
+      i--;
+    }
+  }
+}
+
+struct S1 { // NON_COMPLIANT
+  int i;
+};
+
+void f10() { struct S1 l1; }
+
+void f11() {
+  struct S2 { // COMPLIANT
+    int i;
+  } l1;
+}
+
+struct S3 {
+  int i;
+};
+
+struct S4 { // NON_COMPLIANT; single use in function f13
+  int i;
+};
+
+void f15() {
+  int i; // COMPLIANT
+
+  if (i == 0) {
+    i++;
+  }
+}
+
+void f17() {
+  int i; // COMPLIANT
+  int *ptr;
+  {
+    // Moving the declaration of i into the reduced scope will result in a
+    // dangling pointer
+    ptr = &i;
+  }
+  *ptr = 1;
+}

c/misra/src/rules/RULE-5-2/IdentifiersDeclaredInTheSameScopeNotDistinct.ql

@@ -0,0 +1,38 @@
+/**
+ * @id c/misra/identifiers-declared-in-the-same-scope-not-distinct
+ * @name RULE-5-2: Identifiers declared in the same scope and name space shall be distinct
+ * @description Using nondistinct identifiers results in undefined behaviour.
+ * @kind problem
+ * @precision very-high
+ * @problem.severity warning
+ * @tags external/misra/id/rule-5-2
+ *       correctness
+ *       maintainability
+ *       readability
+ *       external/misra/obligation/required
+ */
+
+import cpp
+import codingstandards.c.misra
+import codingstandards.cpp.Identifiers
+
+from InterestingIdentifiers d, InterestingIdentifiers d2
+where
+  not isExcluded(d, Declarations5Package::identifiersDeclaredInTheSameScopeNotDistinctQuery()) and
+  not isExcluded(d2, Declarations5Package::identifiersDeclaredInTheSameScopeNotDistinctQuery()) and
+  //this rule does not apply if both are external identifiers
+  //that is covered by RULE-5-3
+  not (
+    d instanceof ExternalIdentifiers and
+    d2 instanceof ExternalIdentifiers
+  ) and
+  d.getNamespace() = d2.getNamespace() and
+  d.getParentScope() = d2.getParentScope() and
+  not d = d2 and
+  d.getLocation().getStartLine() >= d2.getLocation().getStartLine() and
+  //first 63 chars in the name as per C99
+  d.getSignificantNameComparedToMacro() = d2.getSignificantNameComparedToMacro() and
+  not d.getName() = d2.getName()
+select d,
+  "Identifer " + d.getName() + " is nondistinct in characters at or over 63 limit, compared to $@",
+  d2, d2.getName()

c/misra/src/rules/RULE-8-5/ExternalObjectOrFunctionNotDeclaredInOneFile.ql

@@ -0,0 +1,43 @@
+/**
+ * @id c/misra/external-object-or-function-not-declared-in-one-file
+ * @name RULE-8-5: An external object or function shall be declared once in one and only one file
+ * @description Declarations in multiple files can lead to unexpected program behaviour.
+ * @kind problem
+ * @precision very-high
+ * @problem.severity warning
+ * @tags external/misra/id/rule-8-5
+ *       correctness
+ *       external/misra/obligation/required
+ */
+
+import cpp
+import codingstandards.c.misra
+
+from DeclarationEntry de, DeclarationEntry otherDeclaration, string kind
+where
+  not isExcluded(de, Declarations5Package::externalObjectOrFunctionNotDeclaredInOneFileQuery()) and
+  //this rule applies to non-defining declarations only
+  not de.isDefinition() and
+  not otherDeclaration.isDefinition() and
+  exists(Declaration d |
+    de.getDeclaration() = d and
+    otherDeclaration.getDeclaration() = d and
+    de.getFile() != otherDeclaration.getFile()
+  ) and
+  (
+    de.getDeclaration() instanceof Function and kind = "function"
+    or
+    de.getDeclaration() instanceof Variable and
+    not de.getDeclaration() instanceof Parameter and
+    kind = "variable"
+  ) and
+  // Apply an ordering based on location to enforce that (de1, de2) = (de2, de1) and we only report (de1, de2).
+  (
+    de.getFile().getAbsolutePath() < otherDeclaration.getFile().getAbsolutePath()
+    or
+    de.getFile().getAbsolutePath() = otherDeclaration.getFile().getAbsolutePath() and
+    de.getLocation().getStartLine() < otherDeclaration.getLocation().getStartLine()
+  )
+select de,
+  "The " + kind + " declaration " + de.getName() +
+    " is declared in multiple files and has an additional $@.", otherDeclaration, "declaration"

c/misra/src/rules/RULE-8-8/MissingStaticSpecifierFunctionRedeclarationC.ql

@@ -0,0 +1,22 @@
+/**
+ * @id c/misra/missing-static-specifier-function-redeclaration-c
+ * @name RULE-8-8: If a function has internal linkage then all re-declarations shall include the static storage class
+ * @description If a function has internal linkage then all re-declarations shall include the static
+ *              storage class specifier to make the internal linkage explicit.
+ * @kind problem
+ * @precision very-high
+ * @problem.severity warning
+ * @tags external/misra/id/rule-8-8
+ *       readability
+ *       external/misra/obligation/required
+ */
+
+import cpp
+import codingstandards.c.misra
+import codingstandards.cpp.rules.missingstaticspecifierfunctionredeclarationshared.MissingStaticSpecifierFunctionRedeclarationShared
+
+class MissingStaticSpecifierFunctionRedeclarationCQuery extends MissingStaticSpecifierFunctionRedeclarationSharedSharedQuery {
+  MissingStaticSpecifierFunctionRedeclarationCQuery() {
+    this = Declarations5Package::missingStaticSpecifierFunctionRedeclarationCQuery()
+  }
+}

c/misra/src/rules/RULE-8-8/MissingStaticSpecifierObjectRedeclarationC.ql

@@ -0,0 +1,27 @@
+/**
+ * @id c/misra/missing-static-specifier-object-redeclaration-c
+ * @name RULE-8-8: If an object has internal linkage then all re-declarations shall include the static storage class
+ * @description If an object has internal linkage then all re-declarations shall include the static
+ *              storage class specifier to make the internal linkage explicit.
+ * @kind problem
+ * @precision very-high
+ * @problem.severity warning
+ * @tags external/misra/id/rule-8-8
+ *       readability
+ *       external/misra/obligation/required
+ */
+
+import cpp
+import codingstandards.c.misra
+
+from VariableDeclarationEntry redeclaration, VariableDeclarationEntry de
+where
+  not isExcluded(redeclaration,
+    Declarations5Package::missingStaticSpecifierObjectRedeclarationCQuery()) and
+  de.hasSpecifier("static") and
+  de.getDeclaration().isTopLevel() and
+  redeclaration.getDeclaration() = de.getDeclaration() and
+  not redeclaration.hasSpecifier("static") and
+  de != redeclaration
+select redeclaration, "The redeclaration of $@ with internal linkage misses the static specifier.",
+  de, de.getName()

c/misra/src/rules/RULE-8-9/UnnecessaryExposedIdentifierDeclarationC.ql

@@ -0,0 +1,22 @@
+/**
+ * @id c/misra/unnecessary-exposed-identifier-declaration-c
+ * @name RULE-8-9: An object should be defined at block scope if its identifier only appears in a single function
+ * @description An identifier declared to be an object or type shall be defined in a block that
+ *              minimizes its visibility to prevent any accidental use of the identifier.
+ * @kind problem
+ * @precision high
+ * @problem.severity warning
+ * @tags external/misra/id/rule-8-9
+ *       correctness
+ *       external/misra/obligation/advisory
+ */
+
+import cpp
+import codingstandards.c.misra
+import codingstandards.cpp.rules.unnecessaryexposedidentifierdeclarationshared.UnnecessaryExposedIdentifierDeclarationShared
+
+class UnnecessaryExposedIdentifierDeclarationCQuery extends UnnecessaryExposedIdentifierDeclarationSharedSharedQuery {
+  UnnecessaryExposedIdentifierDeclarationCQuery() {
+    this = Declarations5Package::unnecessaryExposedIdentifierDeclarationCQuery()
+  }
+}

c/misra/test/rules/RULE-5-2/IdentifiersDeclaredInTheSameScopeNotDistinct.expected

@@ -0,0 +1 @@
+| test.c:8:5:8:68 | iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyB | Identifer iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyB is nondistinct in characters at or over 63 limit, compared to $@ | test.c:2:5:2:68 | iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyA | iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyA |

c/misra/test/rules/RULE-5-2/IdentifiersDeclaredInTheSameScopeNotDistinct.qlref

@@ -0,0 +1 @@
+rules/RULE-5-2/IdentifiersDeclaredInTheSameScopeNotDistinct.ql

c/misra/test/rules/RULE-5-2/test.c

@@ -0,0 +1,26 @@
+extern int
+    iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyA; // NON_COMPLIANT
+                                                                      // -
+                                                                      // length
+                                                                      // 64
+
+static int
+    iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyB; // NON_COMPLIANT
+                                                                      // -
+                                                                      // length
+                                                                      // 64
+
+void f() {
+  int iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjyszmcsylyohvqaosjbqyyC; // COMPLIANT
+                                                                        // -
+                                                                        // length
+                                                                        // 64
+                                                                        // but
+                                                                        // diff
+                                                                        // scope
+}
+
+static int
+    iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjy_C; // COMPLIANT length <63
+static int
+    iltiqzxgfqsgigwfuyntzghvzltueatcxqnqofnnvjy_D; // COMPLIANT length <63

c/misra/test/rules/RULE-8-5/ExternalObjectOrFunctionNotDeclaredInOneFile.expected

@@ -0,0 +1,2 @@
+| test.c:8:12:8:13 | declaration of g3 | The variable declaration g3 is declared in multiple files and has an additional $@. | test1.c:1:12:1:13 | declaration of g3 | declaration |
+| test.h:1:12:1:12 | declaration of g | The variable declaration g is declared in multiple files and has an additional $@. | test1.h:1:12:1:12 | declaration of g | declaration |

c/misra/test/rules/RULE-8-5/ExternalObjectOrFunctionNotDeclaredInOneFile.qlref

@@ -0,0 +1 @@
+rules/RULE-8-5/ExternalObjectOrFunctionNotDeclaredInOneFile.ql

c/misra/test/rules/RULE-8-5/test.c

@@ -0,0 +1,8 @@
+#include "test.h"
+#include "test1.h"
+
+int g = 1; // COMPLIANT
+
+extern int g1; // COMPLIANT
+
+extern int g3; // NON_COMPLIANT

c/misra/test/rules/RULE-8-5/test.h

@@ -0,0 +1,3 @@
+extern int g; // NON_COMPLIANT
+
+int g2; // COMPLIANT

c/misra/test/rules/RULE-8-5/test1.c

@@ -0,0 +1 @@
+extern int g3; // NON_COMPLIANT

c/misra/test/rules/RULE-8-5/test1.h

@@ -0,0 +1,3 @@
+extern int g; // NON_COMPLIANT
+
+int g2; // COMPLIANT

c/misra/test/rules/RULE-8-8/MissingStaticSpecifierFunctionRedeclarationC.testref

@@ -0,0 +1 @@
+cpp/common/test/rules/missingstaticspecifierfunctionredeclarationshared/MissingStaticSpecifierFunctionRedeclarationShared.ql

c/misra/test/rules/RULE-8-8/MissingStaticSpecifierObjectRedeclarationC.expected

@@ -0,0 +1 @@
+| test.c:2:12:2:12 | declaration of g | The redeclaration of $@ with internal linkage misses the static specifier. | test.c:1:12:1:12 | definition of g | g |

c/misra/test/rules/RULE-8-8/MissingStaticSpecifierObjectRedeclarationC.qlref

@@ -0,0 +1 @@
+rules/RULE-8-8/MissingStaticSpecifierObjectRedeclarationC.ql

c/misra/test/rules/RULE-8-8/test.c

@@ -0,0 +1,8 @@
+static int g = 0;
+extern int g; // NON_COMPLIANT
+
+static int g1;
+static int g1 = 0; // COMPLIANT
+
+int g2;
+int g2 = 0; // COMPLIANT

c/misra/test/rules/RULE-8-9/UnnecessaryExposedIdentifierDeclarationC.testref

@@ -0,0 +1 @@
+c/common/test/rules/unnecessaryexposedidentifierdeclarationshared/UnnecessaryExposedIdentifierDeclarationShared.ql